HYDRAULIC NETWORK MODELING TO ANALYZE STREAM FLOW EFFECTIVENESS ON HEAT TRANSFER PERFORMANCE OF SHELL AND TUBE HEAT EXCHANGERS

In this article, stream flow effectivness is based on hydraulic network studied in the shell-side of a shell and tube heat exchange as a case study. For an appropriate heat exchangers rating design to meet a specified duty, it's better to consider each stream flow separately. Using the hydraulic network principals, a set of the correlations for calculating different stream flow rates in the cross and window area, leakage from tube-bundle and shell-baffle bypass are suggested. By the presented correlations, the actual flow direction and different stream flow rates of shell-side fluid for calculating of shell-side heat transfer and pressure drop in different regions between adjacent baffles has been taken into account. Also, the effects of each stream flow in each baffle section on the overall heat transfer coefficient (HTC) and pressure drop could be investigated. The comparison results of using these correlations and results of published values, like Bell-Delaware method and Kern correlations, is reasonable, which can be used in the optimum design of shell and tube heat exchangers with segmental baffles. Also, according to the results, the cross flow stream show much better heat transfer performance with lower pressure drop behavior than window stream at the same mass flow rates. Average heat transfer performance of window-section is almost 7-12% of overall heat transfer performance for studied case study. doi: 10.5829/ije.2017.30.06c.11